RTSP推流增加L16动态payload type支持(RFC 3551 Section 4.5.11, RFC 2586)

src/Extension/L16.h

@@ -0,0 +1,74 @@
+/*
+ * Copyright (c) 2016 The ZLMediaKit project authors. All Rights Reserved.
+ *
+ * This file is part of ZLMediaKit(https://github.com/xiongziliang/ZLMediaKit).
+ *
+ * Use of this source code is governed by MIT license that can be found in the
+ * LICENSE file in the root of the source tree. All contributing project authors
+ * may be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef ZLMEDIAKIT_L16_H
+#define ZLMEDIAKIT_L16_H
+
+#include "Frame.h"
+#include "Track.h"
+
+namespace mediakit{
+
+/**
+ * L16音频通道
+ */
+class L16Track : public AudioTrackImp{
+public:
+    typedef std::shared_ptr<L16Track> Ptr;
+    L16Track(int sample_rate, int channels) : AudioTrackImp(CodecL16,sample_rate,channels,16){}
+
+private:
+    //克隆该Track
+    Track::Ptr clone() override {
+        return std::make_shared<std::remove_reference<decltype(*this)>::type >(*this);
+    }
+    //生成sdp
+    Sdp::Ptr getSdp() override ;
+};
+
+/**
+ * L16类型SDP
+ */
+class L16Sdp : public Sdp {
+public:
+    /**
+     * L16采样位数固定为16位
+     * @param codecId CodecL16
+     * @param sample_rate 音频采样率
+     * @param payload_type rtp payload
+     * @param bitrate 比特率
+     */
+    L16Sdp(CodecId codecId,
+            int sample_rate,
+            int channels,
+            int bitrate = 128,
+            int payload_type = 98) : Sdp(sample_rate,payload_type), _codecId(codecId){
+        _printer << "m=audio 0 RTP/AVP " << payload_type << "\r\n";
+        if (bitrate) {
+            _printer << "b=AS:" << bitrate << "\r\n";
+        }
+        _printer << "a=rtpmap:" << payload_type << " L16/" << sample_rate  << "/" << channels << "\r\n";
+        _printer << "a=control:trackID=" << (int)TrackAudio << "\r\n";
+    }
+
+    string getSdp() const override {
+        return _printer;
+    }
+
+    CodecId getCodecId() const override {
+        return _codecId;
+    }
+private:
+    _StrPrinter _printer;
+    CodecId _codecId;
+};
+
+}//namespace mediakit
+#endif //ZLMEDIAKIT_L16_H